Means for signaling from captive balloons.



H. w. NICHOLS. MEANS FOR SlGNALI Nu' FROM CAPTIVE BALLOONS.

APPLICATION FILED FEB. 16. I91

Patented Mar. 11,1919.

To all whom it may concern:

ratus for signaling.

UNITED STATES PATENT oFFioEi HAROLD WQNICHOLS, OF MAPLEWOOD, NEW JERSEY,ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y.,A CORPORATION OF NEW YORK.

. MEANS FOR SIGNALING- FROM CAPTIVE BALLOONS.

Application filed l ebruary 16, 1917. Serial No. 148,998

Be it known that I, HAROLD W. NIcHoLs, a citizen of the United States,residing at Mapllewood, in the county of Essex and State of ew Jersey,have invented certain new and useful Improvements in Means for Signalingfrom Captive Balloons, of which the following is a full, clear, concise,and exact description.

This invention relates to means and appa- More particularly, it relatesto means for establishing communication between an anchored balloon andthe earth.

Balloons, such as are used for observation purposes, are generallyanchored to earth by some suitable means, such as a single metalliccable, for controlling theheight of ,the balloon above the ground. Incase of such anchored balloons, it is often very desirable to have somemeans of intercom-munication with the ground without complicating theanchoring apparatus thereby.

The object of this invention. is to furnish a simple and efficient meansfor carrying on such communication without introducing any additionalconductors between the balloon and the earth, and without addingappreciably to the weight supported by the balloon.

For the accomplishment of this purpose, this invention employs theconducting qualities of the) single cable connecting the balloon toearth as one side of a signaling circult, and completes the circuit bymeans of the capacity between the balloon and the ground. A source ofvoltage for said circuit is' provided at the grounded end of theanchored strand, and, at both the earth and the balloon, means areprovided for varying the current in said circuit in accordance with thesignals to be sent, and for detecting said variations. V

For the better understanding of this invention reference is made to theaccompanying drawings, in which Figures 1 and 2 illustrate twoembodiments of this invention; and Fig. 3 illustrates means forincreasing the capacity of the balloon with respect to the earth,therebyproviding for a more efficient transmission of the signals. Fig.1 illustrates this invention as adapted to a telegraphic signalingsystem in which the signaling at both the balloon and the g ound isaccomplished by varying the elec- Specification of Letters Patent.

rammed Mar. 11,1919.

at the The balloon 4L is shown anchored to the earth by means of theconducting cable 5. The capacity between the conductive surface of theballoon and the ground is represented by the condenser 6. Thecombination of the cable and the capacity of the balloon with respect tothe earth comprises ;tlie complete telegraphic circuit for which asource of alternating current? is provided. It is preferable that thesonrce 7 In order to rovide for intercommimication between t e balloonand the ground,-

" trical energy from a single source situated keys ll, 12 and l3 areprovided for making and breaking the circuit. If, now, it is desired tosignal from the earth to the balloon, key 13 is closed and key 11 is.operated in accordance with the signals to be sent, thereby causingchanges in the alternating current surging to and from the ballooncapacity. Corresponding changes will occur in the indicating instrument9. If it is desired to signal fromthe balloon to the earth, key

11 is closed, and key 12 is operated in accordance wlth the signals tobe transmitted, while key 13 remains open. Opening and closing key 12causes variations in the curas constituting a transmitting antenna of a"wireless system, and that, by breaking the circuit betweenthe balloonand the 'cable by means of the key 12, the effective length of theantenna is varied, thereby changing correspondingly the current flowingtherein.

It is, therefore, advantageous to have the grounded capacity of theballoon as large as.

In order to furnish means at the upper end of the cable for varying. thecurrent flowing therethrough, Wine insulating J the earth.

means of suitable strength? shown here as a porcelain insulator 14, isprovided for maintaining the anchorage of the balloon, while allowingfor the breaking of the conductive connection between the balloon andThis insulator may be located within the basket 15 or may be somedistance below as shown in the drawing. Inthe latter case it would thenbe preferable to have the lead' wires to the keys 12 and 13 andinstrument 90f sufficient length to enable the ap pa-ratus to beconveniently located for the operator in the basket. 16is a winch onwhich the cable may be wound or unwound, thereby providing means forlowerin the balloon or allowing it to rise. This winch, although restingon the ground, is insulated therefrom. The conductive connection be-"tween the balloon and the ground is continued through the,, part 20 ofthe cable,

the inductance 19 and "the generator 7 to the ground connection 21. Thispart of the cable is shown to be electrically connected to the main partof the cable by means of the adjust-able contact 22. It is apparent,however, that the contact from the portion 20 may be to any part of thewinch which is electrically connected to the cable 5. The variableinductance 19 may be used if desired for. the purpose of tuning thesignaling circuit to the frequency of the generator 7, which tuning maybe done either with key 12 open or with it closed. In order to insuremaximum sensitiveness when si aling to the balloon, it is preferablethat the tuning be made with key 12 open and key 13 closed. This tuningmay be -accom plished by adjusting the variable inductance 19 until theinstrument 8 indicates a. maximum current value. Any suitable insulatedmeans, other than the winch illustrated, may be employed on which thecable may be wound.

'Fig. 2 illustrates the system as adapted for telephonic communicationbetween the ground and the balloon. As in Fig. 1, the signaling circuitconsists of the cable 5, connecting the balloon 4 to earth, and thecapacity of said balloon to earth, represented by the condenser 6. 25 isa source of power for said circuit, shown hre as a source of highfrequency oscillations. By means of transformers 26 and 27, theoscillations from the source 25 are impressed upon circuits 28, 29 and30, 31, respectively.

Circuits 28 and 30 are each provided with \a suitable telephonetransmitter, 33 and 34,-

respectively. Included in circuit 31 is a wave detector 35 and areceiver of electrical oscillations 36 which are shunted bymeans of acondenser '37. Similarly, circuit 29 includes a wave detector 38 and areceiver 39 which are shunted by means of condenser 42. If, now, it isdesired to signal from the balloon to the ground, the impedance ofpedance cause corresponding changes in the efi'ective lmpe-dance of thesignaling circuit, and, consequently, corresponding variations occurinthe amplitude of the oscillations in said signaling circuit. By means oftransformer 26 at the grounded end of the cable these changes affect thecircuit 29 containing the detector 38. Rectified currents .then actuatethe receiver 39, giving rise to audio-frequency oscillationscorresponding to the signals transmitted. Similarly, if it isdesired tocommunicate from the ground to the balloon, the oscillations in circuit28 are varied in accordance with the audio-frequency oscillations fromthe transmitter '33, which variations, by means of thetransformers 26and 27 and the signaling circuit, are impressed upon the detector 35.The rectifiedcurrents from said detector then actuate the receiver 36.

As in Fig. 1, a winch 16 is provided for winding or unwinding the cable.In order to allow the transformer winding 27.to be free from thenecessary tension on the cable, an insulating means 40 is provided nearthe balloon end of the cable capable of withstanding such tension. Thetransformer 27 1s shunted around this insulation so that the conductingpath to the earth is not broken. From the reel the conductive path leadsthrough adjustable contact 22 and inductance 41 to the ground connection21. The variable inductance *1 may be used, if desired, for the purposeof tuning the signaling circuit to the frequency of the generator 25,and thereby increasing the sensitivleness of the signaling circuit tothe signa s.

In order to insure maximum sensitiveness system to have the capacity ofthe ballon to earth rather large in value. If the network 44' should be,made of insulation material such as a cordor rope netting instead of aWire network, some means should be employed for increasing theconductive surface of the balloon. Obviously, one way of so doing wouldbe to make the entire surface of the balloon conductive, by sheets oftin-foil,

for example Fig. 3, however, shows two more convenlent methods foraccomplishing the same result. .One method is by means of a conductingnetwork consisting of the wires 45 and 46 wound around the balloon atright angles to each other, and connected to the cable proper by meansof the conductor 47. It is ob.- ious, however, that the network may beof any suitable complexity. What is desned is to increase the capacityof that part of the system above the key 12 of Fig. 1 or the transformer27 of Fig. 2 so as to make the change in current as large as possiblewhen the signals are being sent. Therefore, this increase may also beaccomplished by simply connecting a second balloon 48 by ametallic'conductor 49 either to the conductive network of the firstballoon, as shown in Fig. 3, or to the anchoring cable proper.'

It is obvious that the signaling system illustrated by these drawingsmay undergo various modifications without departing in any wise from thespirit of this invention as set forth in the appended claims.

What is claimedis:

1. An electric conductor having only one end grounded, means havingappreciable capacity to ground of said conductor, an electric circuitcomprising said conductor and said capacity means, means for signalingover said circuit comprising a source of electrical energy near thegrounded end of said conductor, means at the ungrounded end for varyingthe power from said source in accordance with the signals to betransmitted, and means at the grounded end for detecting saidvariations.

2. In a system for signaling, means having appreciable capacity toearth, an anchoring cable connecting said means to earth, an electriccircuit comprising said means and said cable, means for signaling oversaid circuit comprising a source of alternating current voltage at thegrounded end of said cable, means associated with said capacity meansfor changing the power from said source, and an indicator of said changenear the ground.

3. In a signaling system, an aerial vessel, a single conductorconnecting said vessel to earth, an electric circuit comprising saidconductor and the capacity of said vessel to earth, a single source-ofalternating curat the ungrounded end rent voltage for said circuit atthe grounded, and of said conductor, means near the ground for changingthe flow of current in said conductor and an indicator of said change insaid vessel.

4:. An electric conductor of variable length having only one endgrounded, means having appreciable capacity to ground at the ungroundedend of said conductor, an electric circuit comprising said conductor andsaid capacitytmeans, said circuit comprising a source of alternatingcurrent voltage near the grounded end of said conductor, means fortuning said circuit to the frequency of said source, means at theungrounded end for varying the power from said source in accordance withthe signals to be transmitted, and means at the grounded end fordetecting said variations.

5. In a signaling system, an aerial vessel, a single conductorconnecting said vessel to earth, means comprising a second aerial vesselattached to said first vessel for increasing the capacity of said firstnamed vessel to ground, an electric circuit comprising said conductorand the capacity of said vessels to ground, a single source ofalternating current voltage for said circuit at the grounded end of saidconductor, means near the ground for changing the flow of current insaid conductor, and an indicator of said change in said first vessel.

6. In a signaling system, an aerial vessel, means comprising a singleconductor for anchoring said vessel to the earth, an electric circuitcomprising said conductor, said vessel and the capacity the ground, asource of current at the grounded end of said conductor, means at oneend of said conductor for varying the current in said circuit inaccordance with the signals to be transmitted, and means at the otherend of said conductor for detecting said variations, thereby providingfor intercommunication between said vessel and the earth.

In witness whereof, I hereunto subscribe my name this 15th day ofFebruary, A. 'D.,

HAROLD W. NICHOLS.

means for signaling over 7 ,7

between said vessel and

